include/sparse_format.h

   1 /* SPDX-License-Identifier: BSD-3-Clause */
   2 /*
   3  * This is from the Android Project,
   4  * Repository: https://android.googlesource.com/platform/system/core
   5  * File: libsparse/sparse_format.h
   6  * Commit: 28fa5bc347390480fe190294c6c385b6a9f0d68b
   7  * Copyright (C) 2010 The Android Open Source Project
   8  */
   9
  10 #ifndef _LIBSPARSE_SPARSE_FORMAT_H_
  11 #define _LIBSPARSE_SPARSE_FORMAT_H_
  12 #include "sparse_defs.h"
  13
  14 typedef struct sparse_header {
  15   __le32        magic;          /* 0xed26ff3a */
  16   __le16        major_version;  /* (0x1) - reject images with higher major versions */
  17   __le16        minor_version;  /* (0x0) - allow images with higer minor versions */
  18   __le16        file_hdr_sz;    /* 28 bytes for first revision of the file format */
  19   __le16        chunk_hdr_sz;   /* 12 bytes for first revision of the file format */
  20   __le32        blk_sz;         /* block size in bytes, must be a multiple of 4 (4096) */
  21   __le32        total_blks;     /* total blocks in the non-sparse output image */
  22   __le32        total_chunks;   /* total chunks in the sparse input image */
  23   __le32        image_checksum; /* CRC32 checksum of the original data, counting "don't care" */
  24                                 /* as 0. Standard 802.3 polynomial, use a Public Domain */
  25                                 /* table implementation */
  26 } sparse_header_t;
  27
  28 #define SPARSE_HEADER_MAGIC     0xed26ff3a
  29
  30 #define CHUNK_TYPE_RAW          0xCAC1
  31 #define CHUNK_TYPE_FILL         0xCAC2
  32 #define CHUNK_TYPE_DONT_CARE    0xCAC3
  33 #define CHUNK_TYPE_CRC32    0xCAC4
  34
  35 typedef struct chunk_header {
  36   __le16        chunk_type;     /* 0xCAC1 -> raw; 0xCAC2 -> fill; 0xCAC3 -> don't care */
  37   __le16        reserved1;
  38   __le32        chunk_sz;       /* in blocks in output image */
  39   __le32        total_sz;       /* in bytes of chunk input file including chunk header and data */
  40 } chunk_header_t;
  41
  42 /* Following a Raw or Fill or CRC32 chunk is data.
  43  *  For a Raw chunk, it's the data in chunk_sz * blk_sz.
  44  *  For a Fill chunk, it's 4 bytes of the fill data.
  45  *  For a CRC32 chunk, it's 4 bytes of CRC32
  46  */
  47
  48 #endif